code: def test_outer_join_indexer(self, dtype):
      indexer = libjoin.outer_join_indexer
  
      left = np.arange(3, dtype=dtype)
      right = np.arange(2, 5, dtype=dtype)
      empty = np.array([], dtype=dtype)
  
      result, lindexer, rindexer = indexer(left, right)
      assert isinstance(result, np.ndarray)
      assert isinstance(lindexer, np.ndarray)
      assert isinstance(rindexer, np.ndarray)
      tm.assert_numpy_array_equal(result, np.arange(5, dtype=dtype))
      exp = np.array([0, 1, 2, -1, -1], dtype=np.intp)
      tm.assert_numpy_array_equal(lindexer, exp)
      exp = np.array([-1, -1, 0, 1, 2], dtype=np.intp)
      tm.assert_numpy_array_equal(rindexer, exp)
  
      result, lindexer, rindexer = indexer(empty, right)
      tm.assert_numpy_array_equal(result, right)
      exp = np.array([-1, -1, -1], dtype=np.intp)
      tm.assert_numpy_array_equal(lindexer, exp)
      exp = np.array([0, 1, 2], dtype=np.intp)
      tm.assert_numpy_array_equal(rindexer, exp)
  
      result, lindexer, rindexer = indexer(left, empty)
      tm.assert_numpy_array_equal(result, left)
      exp = np.array([0, 1, 2], dtype=np.intp)
      tm.assert_numpy_array_equal(lindexer, exp)
      exp = np.array([-1, -1, -1], dtype=np.intp)
      tm.assert_numpy_array_equal(rindexer, exp)
  
file_path: pandas/pandas/tests/libs/test_join.py
imports: import numpy
  import pytest
  from pandas._libs import join
  from pandas._libs.join import inner_join, left_outer_join
  import pandas._testing
label_desc: Use image node_id 1 for calling the TestIndexer obj's underlying member method code with example usage: obj.test_outer_join_indexer(dtype) without return types